TEMPORALLY RESOLVED, 2-LINE FLUORESCENCE IMAGING OF NO TEMPERATURE INA TRANSVERSE JET IN A SUPERSONIC CROSS-FLOW

Temporally resolved temperature imaging of a fuel jet in a hot, nonoxi dizing supersonic cross flow is described. The temperature measurement s are obtained with two lasers and two intensified cameras, with a two -line ratio of planar laser-induced fluorescence from nitric oxide, se eded either in the jet or in both the jet and the cross flow. Diagnost ic issues related to the application of the two-line technique in high -speed combustion flows are addressed and include temperature sensitiv ity, transition selection, measurement resolution, fluorescence lifeti me, temporal resolution, and intensifier and camera dynamic-range limi tations. Single-shot and frame-averaged side-view temperature images o f the flow field are presented, and the measurement uncertainties, whi ch are dominated by photon statistical noise and pulse-to-pulse laser fluctuations, are discussed.